Method and apparatus for removing moisture from material by sonic or ultra-sonic energy in combination with centrifugal energy



June 27, 1967 c. STAMOS ETALA 3,327,401

METHOD AND APPARATUS FOR REMOVING MOISTURE FROM MATERIAL BY SONIC OR ULTRA-'SONIC ENERGY IN COMBINATION WITH CENTHIFUGAL ENERGY Filed Oct. 7, 1965 Q u I75 7? I40 M I76 I64 I62 H2 IIGJ I80 172 INVENTORS CHRIS STAMOS I70 PHILIP c. REEVES JAMES D. WENDER,Jr.

ATIORNEY United States Patent 3,327,401 METHOD AND APPARATUS FOR REMOVING MOISTURE FROM MATERIAL BY SONIC 0R ULTRA-SUNIC ENERGY IN COMBINATION WITH CENTRIFUGAL ENERGY Chris Stamos, Chicago, Philip C. Reeves, Arlington Heights, and James D. Wander, Jr., Lombard, 111., assignors to Roberts & Schaefer Company, Division of Thompson-Starrett Company, Inc., Chicago, Ill., a corporation of Illinois Filed Get. 7, 1965, Ser. No. 493,685 14 Claims. (Cl. 34-4) The invention comprehends an improved method and apparatus for removing moisture from material such as coal and other material.

The invention comprehends an improved method and apparatus for dehydrating or drying solid material which includes the use of sonic or ultra-sonic energy in combination with a centrifugal dryer.

There are numerous types of dryers more or less efficient with varying degrees of initial and operating costs. The cost of thermal drying is high in both respects but to date is the only practical means of reducing the moisture content of small sized particles to the lower ranges of dryness. Mechanical dryers such as centrifuges, etc. will not always handle this material and reduce the moisture content to the desired level.

For example, in the drying of coal particles which have been accumulated after coal has been subjected to a washing or cleaning process with the use of known centrifugal dryers it is not possible to reduce the moisture content of the product to a level equivalent to the product obtained by processing in a thermal dryer. As has been heretofore pointed out thermal processing is an expensive method of drying.

The present invention utilizes a centrifugal dryer wherein a sonic field is provided and positioned relative to the moist material being processed in the basket of the dryer, so that the intense, powerful acoustic emissions create a very strong gas turbulence about the liquid carrying particles, and also a succession of compressions and expansions which produces strong surface cavitation. These two actions in part break the surface tension of the moisture, and the whole effect is to facilitate the flow rate from the particles. The sonic waves also provide energy to induce the flow of liquid from the interior of the particles to the surface from whence it is dispersed into the surrounding atmosphere. Thus the invention obviates the disadvantages of prior thermal drying and greatly facilitates and accelerates the removal of moisture by centrifugal forces.

It is an object of the present invention to provide improved means for the removal of moisture from wet material in such a quantity as to render it compatible with ease of handling and accomplishing said object in a more economical manner than has heretofore been accomplished.

In particular, it is an object of the present invention to dry moist material to lower ranges of moisture content than has heretofore been accomplished without resorting to the use of heat in some manner or form.

Another object of the invention is the drying of moist material by the use of a high energy (sonic or ultra sonic) sound field directed toward the moist material to facilitate the moisture removal (either wholly or in part) from the solid particles.

It is a still further object to provide a means for agitating the moist material by exposing it to sonic energy so that due to the particles being continually turned over their surfaces are better exposed to more drying air and on line 1-1 of FIGURE 2, of a sonic-centrifugal dryer.

embodying features of the invention;

FIGURE 2 is a vertical section taken on line 2-2 of FIGURE 1; and

FIGURE 3 is a view similar to FIGURE 2, but illustrating a modified form of the invention.

It will be understood that, for purposes of clarity, certain elements have intentionally been omitted from certain views where they are illustrated to better advantage in other views.

Referring now to the drawings of the invention, and particularly to FIGURES l and 2, it will be seen that a structure embodying one form of the invention is illustrated.

The structure comprises a generally cylindrical housing, indicated generally at 10, mounted on a base 12 and having a pair of horizontally spaced, fiat, round, vertical front and rear side walls 14 and 16, respectively, which are interconnected by a cylindrical, outer wall 18.

Disposed approximately midway between and parallel to the side walls is a flat, round, center wall 20 which divides the interior of housing 10 into first, or front, and second, or rear, chambers 22 and 24, respectively. Center wall 20 has a relatively large, round, central opening which affords communication between chambers 22 and In order to provide access to the interior of the housing, front wall 14 may be provided with a relatively large central opening 26 which may be closed by a flat cover plate 28.

As best seen in FIGURE 2, there is mounted, for rotation about a horizontal axis and for lateral oscillation in a manner hereinafter described, a drum or basket, indicated generally at 30.

[The basket is generally W-shaped, as seen in vertical section, and includes a frusto-conical, perforated outer wall 32 and a frusto-conical inner wall 34 which have converging rear edges'interconnected by an annular, fiat .end wall 36. The central portion of the basket is preferably provided with an integral hub 38 withinwhich is mounted a free end of a horizontally disposed drive shaft 40.

Shaft 40 may be journaled Within a hollow mounting member or journal 42 which is, in turn, mounted in the rear wall 16 of housing 10.

The drive shaft may be driven and oscillated, or reciprocated, axially in any desired manner (not shown in FIGURES l or 2) such as in the manner shown and described in connection with the alternate embodiment is disposed in overlapping or interlocking engagement with a related inner flange 46 of an annular, separator or divider plate 48 which is carried by the housing adjacent center wall 20 of the housing and which serves .to

prevent moisture from passing from the rear to the front chamber and to prevent dried material from passing from the front chamber to rear chamber.

3 Mounted within the housing on a support bar or bracket 56 are a plurality of high energy (sonic or ultra sonic) sound generators 58 which are disposed to generate a radial field F of high energy sound vibrations toward the inner surfaces of the basket outer wall 32 for a purpose hereinafter described.

Wet or moist material, to be dried, indicated at W may be fed into the interior of the housing and basket 30 by means of an input tube 50- which is disposed to extend through an opening 52 in housing outer wall 18. At its lower and rearward extremity tube is connected to an outwardly flaring, funnel shaped deflector 54, the purpose of which is to direct the incoming moist material against the outwardly facing surface of the basket inner wall 34, as shown in FIGURE 2.

As basket 30 is rotated about its horizontal axis on shaft 40 and is also reciprocated or oscillated axially of the shaft, the moist material is driven outwardly by centrifugal force across the basket end wall and against the inner surface of the perforated basket outer wall. As the basket continues to rotate and oscillate moisture is driven from the surface of the material and passes out of the basket through the side wall, and into rear chamber 24 of the housing where it collects and is drained oif through moisture discharge pipe 60.

At the same time that the moisture material deposited on the inner surface of basket wall 32 is being spun about a horizontal axis and oscillated axially to drive the surface moisture from the material and out of the basket through the openings in the basket wall 32, the material is subjected to high energy (sonic or ultra sonic) sound vibrations generated in the sound energy field F by the sound generators 58.

These vibrations increase the amount of moisture which can be drawn to and removed from the surface of the material particles in two ways. The vibrations tend to break the surface tension which holds the moisture on the surface of the individual particle of the moist material so that it can be more easily and thoroughly withdrawn by the centrifugal action of the basket. Also, the vibrations create a oavitationlike action whereby the minute air bubbles in the moisture surrounding the individual particles of material collapse with an implosive force that.

causes severe agitation of the particles and surrounding moisture to free up more moisture which can be withdrawn.

It will be noted that the reciprocating or oscillatory motion of the basket also serves to further agitate the moist material on the walls' of the basket and help in.

preventing the material from forming a solid cake.

As the material has the moisture removed therefrom it becomes lighter and tends to move outwardly, or to the left as seen in FIGURE 2, and out of the basket into chamber 22 where it is collected and drops out of the chamber through a dry material discharge chust 62. Also, the movement of the moist material along the inside of the basket tends to force the lighter, dryer material outwardly along the basket w all 32 untilit reaches the edge of the wall where it passes into chamber 22.

It has been discovered that by the use of the high energy (sonic or.ultra sonic) sound vibrations acting directly on the moist material in combination with the rotative and oscillatory action of the basket a far greater percentage-of the moisture can be removed from the material than is possible with a centrifuge alone without the aid of additional thermal drying means which are hazardous, expensive to operate and maintain and which contribute heavily to air pollution, especially when the dryer is subjected to reducing moisture of material of this size range.

Turning now to FIGURE 3, it will be seen that a moditied form of the invention is shown/The arrangement illustrated in FIGURE 3 is similar to that of the earlier described embodiment in general function and operation,

but has several mechanical differences, the primary one being that the basket rotates on a vertical axis rather than a horizontal axis.

The structure of the embodiment illustrated in FIG- URE 3 includes a generally cylindrical housing mounted upright on a flat horizontal base or base plate 112. The housing includes a pair of parallel, flat, horizontal, round, top and bottom walls 114 and 116, respectively which are interconnected 'by an integral, cylindrical outer or side wall 118.

Concentrically disposed within outer wall 118 is a second cylindrical inner wall 120 which serves to divide the interior of the housing into a pair of concentric first, or outer, and second, or inner, chambers 1 22 and 124, respectively, which are in communication with each other at the top of the housing, because inner wall 120' does not extend all the way to the top of the housing.

Disposed within inner chamber 124 is a drum or basket which is mounted for rotation about a vertical axis and for reciprocating or oscillating movement on said shaft.

Basket 130 includes an upwardly and outwardly sloping, frusto-conical side wall or outer wall 132 and a round, fiat bottom or end wall 136 formed with a central core or hub 138 which receives and is secured to the upper end of a main drive shaft 140.

Shaft 140 is mounted, for rotation about a vertical axis, in a pair of upper and lower mounting members 142 and 144, respectively, which are mounted against the upper and lower surfaces of base plate 112.

At its upper or outer edge basket side wall 132 is provided with an integral flange which extends over the upper edge of inner housing wall 120 to provide a moisture space within chamber 124 between the outer surface of the basket and the inner surface of wall 120.

Moist material, to be dried, may be fed into the basket through material intake tube which is mounted to extend vertically through an opening 152 is cover plate 128. At its lower extremity tube 150 is flared outwardly in an annular, frusto-conical shape as at 154 to permit the moist material to be distributed uniformly against the end or bottom wall 136 of the basket.

Mounted within the inner chamber of the housing around the intake tube is a support bracket or mounting ring 156 on which are mounted a plurality of high energy (sonic or ultra-sonic) sound generators 158 which are disposed at a proper angle to direct a field F of high energy sound vibrations against the moist material on the inside surface of the basket outer wall 132.

Basket 130 is rotated about a vertical axis on shaft 140 on which is mounted a pulley 160 driven by a pulley belt 162 from a motor (not shown) in a conventional manner, Pulley 160 is mounted on shaft 140 by means of a spline connection as at 164 to permit relative vertical movement therebetween as the shaft is reciprocated vertically.

This movement may be accomplished by means of a cam 166, engageable with the lower end of the shaft, which is secured to a horizontally disposed cam shaft 168 which is journ-ally carried in lower mounting member 144. A pulley 170, driven by a. belt 172, is secured to one end of shaft 168 and may also be driven by a motor (not shown) in a conventional manner.

A horizontal shelf or shield is secured to and projects inwardly from the inside of inner housing wall 120 to form the bottom of the moisture collecting space in inner chamber 126.

In operation, this embodiment is essentially the same as the earlier described embodiment. The moist material is introduced into the basket through the intake tube 150 and passes through lower portion 154 of the 132 Where the moisture is driven from the material through the openings in the perforated side wall and passes out of the housing through discharge pipe 182.

At the same time that the basket is being rotated and oscillated the material is being subjected to high energy (sonic or ultra-sonic) sound vibrations in a manner previously described.

As the dried material moves and is moved upward and outward it passes out of the basket over the top of wall 120 and into the outer housing chamber 122 where it passes through the material discharge chute 184 out of the housing.

Again the oscillating motion agitates the material as the sound vibrations are transmitted to increase the effect of the centrifugal force of the rotating basket in drying the material.

In order to provide additional support for the basket on upper mounting member 142 the basket may be furnished on its under side with a plurality of preferably spring loaded bearings 174.

Also, to limit the cushion relative movement between the basket and the upper mounting member there may be provided a collar 176 secured to shaft 142 and adapted to receive the lower ends of compression springs 177, the upper ends of which are in resilient engagement with the lower surface of mounting member 142.

Additional cushioning means between the housing and base may be provided by means of a plurality of compression springs 178 interposed between the upper surface of base plate 112 and a spring retaining shoulder 179 formed integrally with and projecting outwardly from housing outer side wall 118.

What is claimed is:

1. Apparatus for removing moisture from the surface of moist material, comprising in combination:

(a) an enclosed housing mounted upon a base and having a pairof chambers disposed adjacent each other;

(b) a frusto-oonical basket, open on one end, mounted within one of said chambers and having a perforated side wall, sloping outwardly toward said open end;

(c) a moisture intake tube extending into said housing for depositing particles of moist material against the inside surface of the basket side wall;

(d').a device for producing and directing high energy sound vibrations against the moist material particles on the inside of the basket side wall for breaking the surface tension of the moisture on the material particles to facilitate its removal therefrom;

(e) means for rotating the basket about its axis and for oscillating said basket along said axis to agitate said material and drive said moisture by centrifugal force from said material, through said basket side wall, and into said one chamber and to drive the material, from which the moisture has been removed, out of the open end of said basket and into said other chamber;

(f) means for removing the moisture from said one chamber;

(g) means for removing the material, from which the moisture has been removed, from said other chamber.

2. Apparatus for removing moisture from the surface of moist material, comprising in combination:

(a) an enclosed housing having a pair of chambers disposed adjacent each other;

(b) a basket, open on one end, mounted within one of said chambers and having a perforated side wall;

() a moisture intake tube extending into said housing for depositing particles of moist material against the inside surface of the basket side wall;

(d) a device for producing and directing high energy sound vibrations against the moist material on the inside of the basket side wall for breaking the surface'tension of the moisture on the material particles to facilitate its removal therefrom;

(e) means for rotating the basket about its axis and for oscillating said basket along said axis to agitate said material and drive said moisture by centrifugal force from said material, through said basket side wall, and into said one chamber and to drive the material, from which the moisture has been removed, out of the open end of said basket and into said other chamber;

(f) means for removing the moisture from said one chamber;

(g) means for removing the material, from which the moisture has been removed, from said other chamber,

3. Apparatus for removing moisture from moist material, comprising in combination:

(a) an enclosed housing having a pair of chambers disposed adjacent each other;

(b) a basket, open on one end, mounted within one of said chambers and having a perforated side wall; (c) means for depositing moist material against the inside surface of the basket side wall;

(d) a device for producing and directing high energy sound vibrations against the moist material on the inside of the basket side wall for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(e) means for rotating the basket about its axis and for oscillating said basket along said axis to agitate said material and drive said moisture by centrifugal force from said material, through said basket side wall, and into' said one chamber and to drive the material, from which the moisture has been removed, out of the open end of said basket and into said other chamber;

(f) means for removing the moisture from said one chamber;

. (g) means for removing the material, from which the moisture has been removed, from said other chamber.

4. Apparatus for removing moisture from the surface of moist mateIiaL'compn'sing in combination:

(a) an enclosed housing;

(b) a basket, open at one end, mounted within the housing and having a perforated side wall sloping outwardly toward said open end;

(0) means for depositing moist material against the inside surface of the basket side wall;

(d) a device for directing high energy sound vibrations against the moist material on the inside of the basket side wall for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(e) means for rotating the basket about its axis and for oscillating said basket along said axis to agitate said material and drive said moisture by centrifugal force from said material, through said basket side wall, and to drive the material, from which the moisture has been removed, out of the open end 'of the basket;

(f) means for removing the moisture from said hous- (g) means for removing the material, from which the moisture has been removed, from said housing.

5. Apparatus for removing moisture from the surface of moist material, comprising in combination:

(a) an enclosed housing;

(b) a basket, open at one end, mounted within the housing and having a perforated side wall;

(c) means for depositing moist material against the inside surface of the basket side wall;

((1) a device for directing high energy sound vibrations against the moist material on the inside of the basket side wall for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(e) means for rotating the basket about its axis and for oscillating said basket along said axis to agitate said material and drive said moisture by centrifugal force from said material, through said basket side wall, and to drive the material, from which the moisture has been removed, out of the open end of the basket;

(f) means for removing the moisture from said hous- (g) means for removing the material, from which the moisture has been removed, from said housing.

6. Apparatus for removing moisture from moist material, comprising in combination:

(a) an enclosed housing;

(b) a basket, open at one end, mounted within the housing and having a perforated side wall;

(c) means for depositing moist material against the inside surface of the basket side wall;

(d) a device for directing high energy sound vibrations against the moist material on the inside of the basket side wall for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(e) means for rotating the basket about its axis to drive said moisture by centrifugal force from said material, through said basket side wall, and to drive the material, from which the moisture has been removed, out of the open end of the basket;

(f) means for removing the moisture from said hous- (g) means for removing the material, from which the moisture has been removed, from said housing.

7. Apparatus for removing moisture from the surface of moist material, comprising in combination:

(a) a housing;

(b) a rotatable member mounted within the housing;

(c) means for depositing moist material into the rotatable member;

(d) means for directing high energy sound vibrations against the moist material in the rotatable member for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(e) means for rotating the rotatable member about its axis to drive said moisture by centrifugal force from said material and out of said rotatable member and to drive the material, from which the moisture has been removed, out of said rotatable member;

(f) means for removing the moisture from said hous- (g) means for removing the material, from which the moisture has been removed, from said housing.

8. Apparatus for removing moisture from moist material, comprising in combination:

(a) a rotatable member;

(b) means for depositing moist material into the rotatable member;

(c) means for directing high energy sound vibrations against the moist material in the rotatable member for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

((1) means for rotating the rotatable member about its axis to drive said moisture by centrifugal force from said material and out of said rotatable member and to drive the material, from which the moisture has been removed, out of said rotatable member.

9. A method of removing moisture from the surface of particles of moist material, comprising the steps of:

(a) depositing particles of moist material against the inside surface of a perforated, sloping, side wall of an open ended, rotatable member mounted within one chamber of a housing having a pair of adjacent chambers;

(b) directing high energy sound vibrations against the moist material in the rotatable member for break- 8 ing the surface tension of the moisture on the material to facilitate its removal therefrom;

(c) rotating the rotatable member about its axis and oscillating said member along said axis to agitate said material and drive said moisture by centrifugal force from said material, through said member side wall, and into said one chamber and to drive the material, from which the moisture has been removed, out of the open end of the member and into the other chamber;

(d) removing the moisture from said one chamber of the housing;

(e) removing the material, from which the moisture has been removed, from the other chamber of said housing.

10. A method of removing moisture from the surface of particles of moist material, comprising the steps of:

(a) depositing particles of moist material against the inside surface of a perforated side wall of an open ended rotatable member mounted within a housing;

(b) directing high energy sound vibrations against the moist material in the rotatable member for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(c) rotating the rotatable member about its axis and oscillating said member along said axis to agitate said material and drive said moisture by centrifugal force from said material, through said member side wall, and to drive the material, from which the moisture has been removed, out of the open end of the member;

(d) removing the moisture from the housing;

(e) removing the material, from which the moisture has been removed, from said housing.

11. A method of removing moisture from moist material, comprising the steps of:

(a) depositing moist material against the inside surface of a perforated side wall of a rotatable member mounted within a housing;

(b) directing high energy sound vibrations against the moist material in the rotatable member for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(c) rotating the rotatable member about its axis to drive said moisture by centrifugal force from said material, through said member side wall, and to drive the material, from which the moisture has been removed, out of the member;

(d) removing the moisture from the housing;

(e) removing the material, from which the moisture has been removed, from said housing.

12. A method of removing moisture from the surface of moist material, comprising the steps of:

(a) depositing moist material against the inside surface of a side wall of a rotatable member;

(b) directing high energy sound vibrations against the moist material in the member for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(c) rotating the rotatable member about its axis to drive said moisture by centrifugal force from said material, through said member side Wall, and to drive the material, from which the moisture has been removed, out of the member.

13. A method of removing moisture from the surface of moist material, comprising the steps of:

(a) depositing moist material against the inside surface of a side wall of a rotatable member;

(b) directing high energy sound vibrations against the moist material in the member for breaking the surface tension of the moisture on the material to facilitate its removal therefrom;

(c) rotating the rotatable member about its axis to drive said moisture by centrifugal force from said 9 10 material out of said member and to drive the matedrive said moisture by centrifugal force from said rial, from which the moisture has been removed, out material out of said member.

of the member.

14. A method of removing moisture from moist ma- References Cited terial, p is e steps I 5 UNITED STATES PATENTS (ageld epositmg molst material into the rotatable mem- 2,861,691 11/1958 Linke et a1 210 385 a 2,963,158 12/1960 Jung 210--384 X (b) directing hlgh energy sound vibrations agamst the 3,175,299 4/1965 Boucher 3 I 4 moist material in the member for breaking the surfacitenslon the mist the mammal to 1 FREDERICK L. MATTESON, 111., Primary Examiner. facilitate its removal therefrom, (c) rotating the rotatable member about its axis to JAMES W. WESTHAVER, Examiner. 

14. A METHOD OF REMOVING MOISTURE FROM MOIST MATERIAL, COMPRISING THE STEPS OF: (A) DEPOSITING MOIST MATERIAL INTO THE ROTATABLE MEMBER; (B) DIRECTING HIGH ENERGY SOUND VIBRATIONS AGAINST THE MOIST MATERIAL IN THE MEMBER FOR BREAKING THE SURFACE TENSION OF THE MOISTURE ON THE MATERIAL TO FACILITATE ITS REMOVAL THEREFROM; (C) ROTATING THE ROTATABLE MEMBER ABOUT ITS AXIS TO DRIVE SAID MOISTURE BY CENTRIFUGAL FORCE FROM SAID MATERIAL OUT OF SAID MEMBER. 